Polyphenylene ether-based resin composition containing silicon compound

ABSTRACT

The present invention relates to a polyphenylene ether-based resin composition comprising a polyphenylene ether-based resin and at least one member selected from cage silsesquioxanes and partially cleaved structures of cage silsesquioxanes. The polyphenylene ether-based resin composition of the invention is excellent in heat resistance, mechanical properties, moldability and flame resistance.

This application is the national phase under 35 U.S.C. § 371 of PCTInternational Application No. PCT/JP02/00472 which has an Internationalfiling date of Jan. 23, 2002, which designated the United States ofAmerica.

TECHNICAL FIELD

The present invention relates to a polyphenylene ether-based resincomposition. More specifically, it relates to a polyphenyleneether-based resin composition excellent in moldability and flameresistance, which contains a cage silsesquioxane and/or a partiallycleaved structure thereof.

BACKGROUND ART

Since polyphenylene ether-based resins have a lightweight and areexcellent in impact resistance as compared with metal or glass, theresins have been employed in a variety of fields including automobileparts, household electric appliance parts, and office automationequipment parts. However, since polyphenylene ether resins have a badmoldability, the resins are used not singly but as a mixture with apolystyrene-based resin which is completely compatible. However, theincorporation of the polystyrene-based resin which is more flammablethan the polyphenylene ether-based resins lowers the heat-resistanttemperature of the mixed resin of polyphenylene ether/polystyrene, andalso makes the resin flammable. Therefore, a novel method that enablesmolding a polyphenylene ether-based resin without incorporatingpolystyrene has been desired. Moreover, it has been also desired todevelop a method of achieving both moldability and flame resistance atthe same time.

As methods for imparting flame resistance to polyphenylene ether-basedresins, there have been known methods of adding a halogen-based,phosphorus-based, inorganic or a mixed retardant thereof, and therebyflame resistance has been imparted to some extent. Recently, however, arequest for safety against fire has become particularly important and,at the same time, it has been strongly desired to develop a technologyhaving no environmental problems. Therefore, it has been currentlydesired to develop a novel non-halogen or non-phosphorus flame retardantwhich exhibits a high flame-retarding effect and does not deterioratepractical performance such as mechanical properties of resincompositions. An organic silicon-based flame retardant is proposed as aflame retardant which possibly satisfies these requirements. As examplesthereof, a flame-resistant resin compositions containing a polyphenyleneether-based resin composition and dimethylsilicone are disclosed inJP-B-63-10184, JP-A-64-4656, U.S. Pat. Nos. 4,497,925 and 4,387,176, andJP-A-2-133464. However, the silicone in the above publications has a lowcompatibility with polyphenylene ether-based resins and a lowmoldability. Moreover, the silicone cannot withstand practical use owingto its volatility.

In consideration of such situation, it is an object of the invention toprovide a polyphenylene ether-based resin composition having none of theaforementioned problems, i.e., having an excellent melt flowability andflame resistance and a high heat resistance.

DISCLOSURE OF THE INVENTION

As a result of extensive studies for solving the above problems, thepresent inventors have found that melt flowability and flame resistanceof the resin composition are remarkably enhanced at the same time bymixing a specific cage silsesquioxane compound and/or partially cleavedstructure thereof with a polyphenylene ether-based resin, and they haveaccomplished the invention. Among them, it is noteworthy that theincorporation of a small amount of the specific cage silsesquioxanecompound and/or partially cleaved structure thereof improves theproperties of the polyphenylene ether-based resin to a large extent andhence a far smaller amount of a modifier to be added is sufficient ascompared with the case of a polyphenylene ether/polystyrene-basedpolymer alloy or the like. Therefore, it is confirmed that meltflowability and flame resistance are improved while hardly impairing thehigh heat resistance and excellent mechanical properties intrinsic tothe polyphenylene ether resin in the polyphenylene ether-based resincomposition of the invention. The above characteristics of thecomposition of the invention are industrially very important and arefirst confirmed by the inventors of the present application.

In this connection, the inventors have widely investigated the effect ofincorporating a variety of cage silsesquioxane compounds and partiallycleaved structure thereof into various polymers. As a result, no flameresistance-improving effect was observed in the cases of polybutyleneterephthalate (PBT) (an aromatic condensation polymer), Nylon-66 (analiphatic condensation polymer), and the like. Therefore, theindustrially important finding that the above flame resistance-enhancingeffect and melt moldability-enhancing effect of the invention areexhibited at the same time even by a small amount of the additive is aninnovative finding which was first found by the inventors through thecombination of a specific cage silsesquioxane compound and/or partiallycleaved structure thereof with a polyphenylene ether-based resin.

Namely, the invention relates to the following.

(1) A polyphenylene ether-based resin composition comprising apolyphenylene ether-based resin and at least one of a cagesilsesquioxane and a partially cleaved structure of a cagesilsesquioxane.

(2) The polyphenylene ether-based resin composition described in theabove (1), wherein the cage silsesquioxane is a compound represented bythe general formula (A) and the partially cleaved structure of the cagesilsesquioxane is a compound represented by the general formula (B):[RSiO_(3/2)]_(n)  (A)(RSiO_(3/2))_(l)(RXSiO)_(k)  (B)wherein, in the general formulae (A) and (B), R is selected from ahydrogen atom, an alkoxyl group having 1 to 6 carbon atoms, an aryloxygroup, a substituted or unsubstituted hydrocarbon group having 1 to 20carbon atoms, and a silicon atom-containing group having 1 to 10 siliconatoms, and a plurality of R's may be the same or different; in thegeneral formula (B), X is a group selected from OR₁ (R₁ is a hydrogenatom, an alkyl group, an aryl group, a quaternary ammonium radical),halogen atom and groups defined in the above R, and a plurality of X'smay be the same or different or a plurality of X's in (RXSiO)_(k) may beconnected to each other to form a connected structure; and n is aninteger of 6 to 14, l is an integer of 2 to 12, and k is 2 or 3.

(3) The polyphenylene ether-based resin composition described in theabove (2), wherein the connected structure in the general formula (B) isa connected structure represented by the general formula (1):

wherein Y and Z are selected from the group consisting of the samegroups as those for X, and Y and Z may be the same or different.

(4) The polyphenylene ether-based resin composition described in theabove (2) or (3), wherein the compounds of the general formulae (A) and(B) have a ratio of “the number of R, X, Y, and Z which are aromatichydrocarbon groups” to “the number of all of R, X, Y, and Z” of 93% orless.

(5) The polyphenylene ether-based resin composition described in any oneof the above (2) to (4), wherein at least one of R, X, Y, and Z in thegeneral formulae (A) and (B) is 1) a group containing an unsaturatedhydrocarbon bond or 2) a group having a polar group containing at leastone of a nitrogen atom and an oxygen atom.

(6) The polyphenylene ether-based resin composition described in theabove (3) or (5), wherein the compound of the general formula (B) is acompound represented by the following general formula (B-1):(RSiO_(3/2))_(l)(RX_(a1)SiO)(Rx_(a2)SiO)(Rx_(b)SiO)  (B-1)wherein, in the general formula (B-1), R and l are the same as in thecase of the general formula (B); X_(a1) and X_(a2) are selected from thegroup consisting of the same groups as those for X in the generalformula (B) and X_(a1) and X_(a2) may be connected to each other to forma connected structure represented by the general formula (1-1):

wherein X_(b) is a group selected from a hydroxyl group and—OSi(OH)Y″Z″; Y′, Z′, Y″ and Z″ are selected from the group consistingof the same groups as those for X in the general formula (B); providedthat at least one of X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ in thesame compound is 1) a group containing an unsaturated hydrocarbon bondor 2) a group having a polar group containing a nitrogen atom and/or anoxygen atom and X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ may be the sameor different from each other.

(7) The polyphenylene ether-based resin composition described in theabove (6), wherein at least one of X_(a1), X_(a2), X_(b), Y′, Z′, Y″ andZ″ in the compound of the general formula (B-1) is a group containing anamino group.

(8) A compound represented by the following general formula (B-1):(RSiO_(3/2))_(l)(RX_(a1)SiO)(Rx_(a2)SiO)(RX_(b)SiO)  (B-1)wherein, in the general formula (B-1), R is selected from a hydrogenatom, an alkoxyl group having 1 to 6 carbon atoms, an aryloxy group, asubstituted or unsubstituted hydrocarbon group having 1 to 20 carbonatoms, and a silicon atom-containing group having 1 to 10 silicon atoms,and a plurality of R's may be the same or different; l is an integer of2 to 12; X_(a1) and X_(a2) are selected from the group consisting of thesame groups as those for X in the general formula (B) and X_(a1) andX_(a2) may be connected to each other to form a connected structurerepresented by the general formula (1-1):

wherein X_(b) is a group selected from a hydroxyl group and—OSi(OH)Y″Z″; Y′, Z′, Y″ and Z″ each is a group selected from OR₁ (R₁ isa hydrogen atom, an alkyl group, an aryl group, a quaternary ammoniumradical), halogen atom and groups defined in the above R; provided thatat least one Of X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ in the samecompound is a group having a polar group containing an amino group andX_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ are the same or different fromeach other.

(9) The polyphenylene ether-based resin composition described in any oneof the above (1) to (7), wherein the content of the cage silsesquioxaneand the partially cleaved structure of the cage silsesquioxane is from0.1% by weight to 90% by weight in total.

(10) The polyphenylene ether-based resin composition described in anyone of the above (1) to (7) and (9), wherein the polyphenyleneether-based resin is composed solely of a polyphenylene ether resin.

(11) The polyphenylene ether-based resin composition described in anyone of the above (1) to (7) and (9), wherein the polyphenyleneether-based resin is a polymer alloy of a polyphenylene ether resin andat least one other resin.

(12) The polyphenylene ether-based resin composition described in theabove (11), wherein the polyphenylene ether-based resin is a polymeralloy containing a polyphenylene ether resin and at least one resinselected from a polystyrene-based resin, a polyamide-based resin, apolyester-based resin, a polyolefin-based resin, and a polyethersulfone-based resin.

(13) The polyphenylene ether-based resin composition described in theabove (11) or (12), wherein the content of the polyphenylene ether resinin the polymer alloy is 40% by weight or more.

(14) The polyphenylene ether-based resin composition described in anyone of the above (1) to (7) and (9) to (13), which further contains acyclic nitrogen compound.

(15) A process for producing a molded article of a polyphenyleneether-based resin composition, comprising melt-molding a polyphenyleneether-based resin composition described in any one of the above (1) to(7) and (9) to (14).

(16) A molded article of the polyphenylene ether-based resin compositiondescribed in any one of the above (1) to (7) and (9) to (14).

BEST MODE FOR CARRYING OUT THE INVENTION

The following will describe the invention in detail.

The “polyphenylene ether-based resin composition comprising apolyphenylene ether-based resin and at least one of a cagesilsesquioxane and a partially cleaved structure of the cagesilsesquioxane” of the invention means a composition containing “atleast one of a cage silsesquioxane and a partially cleaved structure ofthe cage silsesquioxane” and a “polyphenylene ether-based resin” asessential constituents. The “polyphenylene ether-based resin” for use inthe invention means a “polyphenylene ether resin and polymer alloycontaining the same”. The “polyphenylene ether resin” for use in theinvention means a homopolymer composed of a repeating unit of thefollowing general formula (2), a copolymer containing a repeating unitof the following general formula (2), or a modified polymer thereof.

wherein R₂, R₃, R₄, and R₅ each represents hydrogen, primary orsecondary lower alkyl, phenyl, aminoalkyl, or hydrocarbon-oxy.

As the polyphenylene ether resin, a polymer having a wide range ofmolecular weight is usable but a homopolymer and/or copolymer having areduced viscosity (0.5 g/dl, chloroform solution, measured at 30° C.) inthe range of preferably 0.15 to 1.0 dl/g is used, the reduced viscositybeing more preferably in the range of 0.20 to 0.70 dl/g, most preferablyin the range of 0.40 to 0.60.

Representative Examples of the polyphenylene ether homopolymers includepoly(1,4-phenylene)ether, poly(2,6-dimethyl-1,4-phenylene)ether,poly(2,5-dimethyl-1,4-phenylene)ether,poly(2-methyl-6-ethyl-1,4-phenylene)ether,poly(2,6-diethyl-1,4-phenylene)ether,poly(2,6-diphenyl-1,4-phenylene)ether,poly(2,3,6-trimethyl-1,4-phenylene)ether, and the like. Of these,particularly preferred is poly(2,6-dimethyl-1,4-phenylene)ether.Examples of the polyphenylene ether copolymers include copolymers of2,6-dimethylphenol and the other phenol (e.g., 2,3,6-trimethylphenol,2,6-diphenylphenol or 2-methylphenol (o-cresol)) and the like. Among theabove various polyphenylene ether resins, preferred arepoly(2,6-dimethyl-1,4-phenylene)ether, a copolymer of 2,6-dimethylphenoland 2,3,6-trimethylphenol and particularly preferred ispoly(2,6-dimethyl-1,4-phenylene)ether.

An example of the process for producing a polyphenylene ether resin foruse in the invention includes a method of oxidative polymerization of2,6-xylenol using a complex of a cuprous salt with an amine described inU.S. Pat. No. 3,306,874 as a catalyst.

Processes described in U.S. Pat. Nos. 3,306,875, 3,257,357 and3,257,358, JP-B-52-17880, and JP-A-50-51197 and JP-A-63-152628 are alsopreferred as processes for producing a polyphenylene ether resin.

The polyphenylene ether resin of the invention may be used as a powderafter the polymerization step as it is, or may be used as pelletsobtained by melt-kneading using an extruder or the like under a nitrogengas atmosphere or non-nitrogen gas atmosphere, under a degassed ornon-degassed condition.

The polyphenylene ether resin of the invention also includes apolyphenylene ether modified with a dienophile compound. Variousdienophile compounds may be used for the modification treatment, butexamples of the dienophile compounds include maleic anhydride, maleicacid, fumaric acid, phenylmaleimide, itaconic acid, acrylic acid,methacrylic acid, methyl arylate, methyl methacrylate, glycidylacrylate, glycidyl methacrylate, stearyl acrylate, styrene and the likecompounds. Furthermore, as a method for modification with thesedienophile compounds, a polyphenylene ether may be functionalized in amelted state under a degassed or non-degassed condition using anextruder or the like in the presence or absence of a radical generator.Alternatively, it may be functionalized in a non-melted state, i.e., inthe temperature range of room temperature to melting point in thepresence or absence of a radical generator. At that time, melting pointof the polyphenylene ether is defined as a peak top temperature of apeak observed in a temperature-heat flow graph obtained at a temperatureelevation rate of 20° C./minute in the measurement on a differentialscanning calorimeter. In the case that two or more peak top temperaturesare present, it is defined as a maximum temperature thereof.

The polyphenylene ether-based resin of the invention may be the abovepolyphenylene ether resin alone or a polymer alloy of the abovepolyphenylene ether resin with the other resin. Examples of the otherresin in this case include polystyrene-based resins such as atacticpolystyrene, syndiotactic polystyrene, high impact polystyrene, anacrylonitrile-styrene copolymer, and the like; polyamide-based resinssuch as Nylon 6,6 and Nylon 6; polyester-based resins such aspolyethylene terephthalate, polytriethylene terephthalate, andpolybutylene terephthalate; polyolefin-based resins such as polyethyleneand polypropylene; polyether sulfone-based resins; and the like. Thepolymer alloy containing the polyphenylene ether resin for use in theinvention may be a polymer alloy obtainable by combining thepolyphenylene ether resin and any one resin selected frompolystyrene-based resins, polyamide-based resins, polyester-basedresins, polyolefin-based resins, polyether sulfone-based resins, and thelike, or a polymer alloy obtainable by combining the polyphenylene etherresin and two or more, plural resins.

In the case that a polymer alloy of the polyphenylene ether resin and aresin selected from polystyrene-based resins, polyamide-based resins,polyester-based resins, polyolefin-based resins, polyether sulfone-basedresins, the content of the polyphenylene ether resin is preferably 40%by weight or more, more preferably 60% by weight or more, particularlypreferably 80% by weight or more based on the total amount of thepolyphenylene ether resin and the resin selected from polystyrene-basedresins, polyamide-based resins, polyester-based resins, polyolefin-basedresins, polyether sulfone-based resins.

In this connection, the content of the polyphenylene ether resin ispreferably 35% by weight or more, more preferably 70% by weight or more,particularly preferably 90% by weight or more based on the total amountof the polyphenylene ether-based resin composition of the invention.

The following will describe the cage silsesquioxane and partiallycleaved structure thereof for use in the invention.

While silica is represented by SiO₂, a silsesquioxane is a compoundrepresented by [R′SiO_(3/2)]. The silsesquioxane is a polysiloxaneusually synthesized by hydrolysis-polycondensation of an R′SiX₃ (R′=ahydrogen atom, an organic group, or a siloxy group, X=a halogen atom oran alkoxy group) type compound. As shapes of molecular arrangement,there are known typically an amorphous structure, a ladder structure, acage (completely condensed cage) structure or a partially cleavedstructure thereof (a structure wherein one silicon atom is removed fromthe cage structure or a structure wherein a part of silicon-oxygen bondsis cleaved), or the like.

The inventors have investigated the effects of incorporating variousorganic silicon compounds to polyphenylene ether-based resins. As aresult, they have found that the incorporation of a cage silsesquioxanehaving a specific structure or/and a partially cleaved structure of thecage silsesquioxane, among various organic silicon compounds, topolyphenylene ether-based resins affords a polyphenylene ether-basedresin composition which is excellent in moldability (or meltflowability) and affords a molded article excellent in flame resistanceand mechanical properties, and thus they have accomplished theinvention.

As an example of specific structure of the cage silsesquioxane for usein the invention, a cage silsesquioxane represented by the followinggeneral formula (A) may be mentioned, for example. Moreover, as anexample of specific structure of the partially cleaved structure of thecage silsesquioxane for use in the invention, a partially cleavedstructure of the cage silsesquioxane represented by the followinggeneral formula (B) may be mentioned, for example. However, thestructure of the cage silsesquioxane or partially cleaved structurethereof for use in the invention is not limited to these structures.[RSiO_(3/2)]_(n)  (A)(RSiO_(3/2))_(l)(RXSiO)_(k)  (B)wherein, in the general formulae (A) and (B), R is selected from ahydrogen atom, an alkoxyl group having 1 to 6 carbon atoms, asubstituted or unsubstituted hydrocarbon group having 1 to 20 carbonatoms, and a silicon atom-containing group having 1 to 10 silicon atoms,and all of R's may be the same or may comprise a plurality of thegroups.

Examples of the cage silsesquioxane represented by the general formula(A) for use in the invention include a type represented by the chemicalformula [RSiO_(3/2)]₆ (the following general formula (3)), a typerepresented by the chemical formula [RSiO_(3/2)]₈ (the following generalformula (4)), a type represented by the chemical formula [RSiO_(3/2)]₁₀(the following general formula (5)), a type represented by the chemicalformula [RSiO_(3/2)]₁₂ (the following general formula (6)), and a typerepresented by the chemical formula [RSiO_(3/2)]₁₄ (the followinggeneral formula (7)).

The value n in the cage silsesquioxane represented by the generalformula (A) [RSiO_(3/2)]_(n) of the invention is an integer of 6 to 14,preferably 8, 10 or 12, more preferably 8, 10 or a mixture of 8 and 10or a mixture of 8, 10, and 12, particularly preferably 8 or 10.

Moreover, in the invention, it is also possible to use a structurewherein a part of silicon-oxygen bonds in the cage silsesquioxane ispartially cleaved, or a structure wherein a part of the cagesilsesquioxane is eliminated, or a partially cleaved structure of thecage silsesquioxane represented by the general formula (B)(RSiO_(3/2))_(l)(RXSiO)_(k) (l is an integer of 2 to 12 and k is 2 or3), which is derived from the above structures.

In the general formula (B), X is a group selected from OR₁ (R₁ is ahydrogen atom, an alkyl group, an aryl group, a quaternary ammoniumradical), halogen atom and groups defined in the above R, and aplurality of X's may be the same or different or a plurality of X's in(RXSiO)_(k) may be connected to each other to form a connectedstructure. Moreover, l is an integer of 2 to 12, preferably an integerof 4 to 10, particularly preferably 4, 6 or 8. k is 2 or 3.

Two or three X's in (RXSiO)_(k) may be connected to the other X's in thesame molecule each other to form a variety of connected structures.Specific examples of the connected structures will be described in thefollowing.

Two X's in the same molecule of the general formula (B) may form anintramolecular connected structure represented by the general formula(1). Furthermore, two X's present in different molecules may beconnected to each other to form a dinuclear structure through theconnected structure represented by the above general formula (1).

wherein Y and Z are selected from the group consisting of the samegroups as those for X, and Y and Z may be the same or different.

Examples of the connected structure represented by the general formula(1) include the following divalent group structures.

Moreover, in the case that two X's in the same molecule in the generalformula (B) is connected to each other to form a connected structure,the connected structure may be a connected structure represented by thegeneral formula (15). Q in the general formula (15) is a substituted orunsubstituted hydrocarbon group having 1 to 20 carbon atoms or ahydrogen atom among the groups for R in the general formulae (A) and (B)(for example, cf. Mat. Res. Soc. Symp. Prac. 1999, 576, 111).

Furthermore, two or three X's in the general formula (B) may beconnected to form a connected structure containing a metal atom otherthan a silicon atom. Examples of the connected structure containing theother metal atom in this case include a connected structure containing abond of [Si—O-metal atom] type, an organometal-type connected structure,or the like. As a specific example of the compound of the generalformula (B) having a connected structure containing another metal atom,a structure wherein one Si in (RSiO_(3/2))_(n) constituting the generalformula (A) is replaced by another metal atom or an organometallic groupmay be mentioned. Moreover, two X's in the general formula (B) may bereplaced with metal atoms other than silicon atoms. Examples of theother metal atom or the metal atom in the organometal-type connectedstructure include Al, Ti, Zr, V, Ta, Cr, Mo, W, Re, Ru, Pt, Sn, Sb, Ga,Tl and the like. The cage silsesquioxane and/or partially cleavedstructure thereof may form a dinuclear structure through theincorporation of these metal atoms (for example, cf. Feher at al.,Polyhedron, 1995, 14, 3239 and Organometallics, 1995, 14, 3920).

Among the above various connected structures in the compoundsrepresented by the general formula (B), the connected structurerepresented by the general formula (1) is easy to synthesize and ispreferable.

Examples of the compounds represented by the general formula (B) for usein the invention include a trisilanol compound which has a structurewherein a part of the general formula (4) is eliminated or a typerepresented by the chemical formula (RSiO_(3/2))₄(RXSiO)₃ synthesizedthereform (e.g., the following general formula (8)), a type wherein twoX's of the three X's in the general formula (8) or (RSiO_(3/2))₄(RXSiO)₃form a connected structure represented by the general formula (1) (e.g.,the following general formula (9)), a type represented by the chemicalformula (RSiO_(3/2))₆(RXSiO)₂ derived from a disilanol compound whereina part of the general formula (4) is cleaved (e.g., the followinggeneral formulae (10) and (11)), a type wherein two X's in the generalformula (10) or (RSiO_(3/2))₆(RXSiO)₂ form a connected structurerepresented by the general formula (1) (e.g., the following generalformula (12)), and the like. The mutual positions of R and X or Y and Zconnected to the same silicon atom in the general formulae (8) to (12)may be exchangeable. Furthermore, two X's present in the differentmolecules may be connected to each other to form a dinuclear structurethrough a variety of the connected structures including the abovegeneral formula (1) as a representative.

Moreover, as a specific example of the compound wherein two or three X'sin the general formula (B) is connected to form a connected structurecontaining a metal atom other than a silicon atom, there may bementioned a compound represented by the chemical formula(RSiO_(3/2))₄(RXSiO)₃ wherein three X's in the compound represented bythe general formula (8) form a connected structure containing a Ti atom(e.g., the following general formula (8-Ti)).

These various cage silsesquioxanes or partially cleaved structuresthereof may be used singly or as a mixture of two or more of them.

The kinds of R in the compounds represented by the general formula (A)and/or the general formula (B) for use in the invention include ahydrogen atom, an alkoxyl group having 1 to 6 carbon atoms, an aryloxygroup, a substituted or unsubstituted hydrocarbon group having 1 to 20carbon atoms, and a silicon atom-containing group having 1 to 10 siliconatoms.

Examples of the alkoxyl group having 1 to 6 carbon atoms include amethoxy group, an ethoxy group, an n-propyloxy group, an i-propyloxygroup, an n-butyloxy group, a t-butyloxy group, an n-hexyloxy group, acyclohexyloxy group, and the like. Examples of the aryloxy group includea phenoxy group, 2,6-dimethylphenoxy group, and the like. The totalnumber of the alkoxyl groups and aryl oxy groups in one molecule of thegeneral formula (A) or (B) is preferably 3 or less, more preferably 1 orless.

Examples of the hydrocarbon group having 1 to 20 carbon atoms includeacyclic or cyclic aliphatic hydrocarbon groups such as methyl ethyl,n-propyl, i-propyl, butyl (n-butyl, i-butyl, t-butyl, sec-butyl),pentyl(n-pentyl, i-pentyl, neopentyl, cyclopentyl, etc.), hexyl(n-hexyl,i-hexyl, cyclohexyl, etc.), heptyl(n-heptyl, i-heptyl, etc.),octyl(n-octyl, i-octyl, t-octyl, etc.), nonyl(n-nonyl, i-nonyl, etc.),decyl(n-decyl, i-decyl, etc.), undecyl(n-undecyl, i-undecyl, etc.), anddodecyl(n-dodecyl, i-dodecyl, etc.) groups; acyclic or cyclic alkenylgroups such as vinyl, propenyl, butenyl, pentenyl, hexenyl,cyclohexenyl, cyclohexenylethyl, norbornenylethyl, heptenyl, octenyl,nonenyl, decenyl, undecenyl, dodecenyl, and styrenyl groups; aralkylgroups such as benzyl, phenethyl, 2-methylbenzyl, 3-methylbenzyl, and4-methylbenzyl groups; aralkenyl groups such as a PhCH═CH— group; arylgroups such as a phenyl group, a tolyl group, and a xylyl group;substituted aryl groups such as a 4-aminophenyl group, a 4-hydroxyphenylgroup, a 4-metoxyphenyl group, and a 4-vinylphenyl group; and the like.

In the case that the ratio of the number of particularly the aliphatichydrocarbon group having 2 to 20 carbon atoms and the alkenyl grouphaving 2 to 20 carbon atoms of these hydrocarbon groups to the totalnumber of R, X, Y, and Z is larger, particularly good melt flowabilityat molding is obtained. Moreover, in the case that R is an aliphatichydrocarbon group and/or an alkenyl group, the number of carbon atoms inR is usually 20 or less, preferably 16 or less, more preferably 12 orless in view of a good balance of melt flowability at molding, flameresistance, and operability.

Furthermore, R for use in the invention may be a group wherein hydrogenatom(s) or a part of main chain skeleton of these various hydrocarbongroups may be partially replaced with substituent(s) selected from polargroups (polar bonds) such as an ether bond, an ester group (bond), ahydroxyl group, a carbonyl group, a carboxylic acid anhydride bond, athiol group, a thioether bond, a sulfone group, an aldehyde group, anepoxy group, an amino group, an amide group (bond), a urea group (bond),an isocyanate group, and a cyano group, or halogen atoms such asfluorine atom, chlorine atom, and bromine atom.

The total number of carbon atoms in the substituted or unsubstitutedhydrocarbon group including its substituent(s) in R in the generalformulae (A) and (B) may be usually 20 or less, preferably 16 or less,particularly preferably 12 or less in view of a good balance of meltflowability at molding, flame resistance, and operability.

As the silicon atom-containing group having 1 to 10 silicon atomsadopted as R, those having a wide variety of structures are adopted, anda group having the following general formula (13) or (14) may bementioned, for example. The number of the silicon atoms in the siliconatom-containing group is usually in the range of 1 to 10, preferably inthe range of 1 to 6, more preferably in the range of 1 to 3. Too many anumber of the silicone atoms is not preferable because the cagesilsesquioxane compound becomes a viscous liquid and is difficult tohandle or purify.

n in the general formula (13) is usually an integer in the range of 1 to10, preferably an integer in the range of 1 to 6, more preferably aninteger in the range of 1 to 3. Moreover, the substituents R₆ and R₇ inthe general formula (13) is a hydrogen atom, a hydroxyl group, an alkoxygroup, a chlorine atom, or an organic group having 1 to 10 carbon atoms,preferably 1 to 6 carbon atoms other than an alkoxy group.

Examples of the alkoxy group include a methoxy group, an ethoxy group, abutoxy group and the like.

As examples of the organic group having 1 to 10 carbon atoms other thanan alkoxy group, various substituted or unsubstituted hydrocarbon groupsmay be mentioned. Specific examples thereof include aliphatichydrocarbon groups such as a methyl group, an ethyl group, a propylgroup, a butyl group and a cyclohexyl group; unsaturated hydrocarbonbond-containing groups such as a vinyl group and a propenyl group;aromatic hydrocarbon groups such as a phenyl group, a benzyl group and aphenethyl group; fluorine-containing alkyl group such as CF₃CH₂CH₂—;polar group-substituted alkyl groups such as an aminoalkyl group; andthe like.

R₈ in the general formula (13) is a hydrogen atom or an organic grouphaving 1 to 20 carbon atoms, preferably 1 to 12 carbon atoms, morepreferably 1 to 8 carbon atoms. Examples of the organic group includealiphatic hydrocarbon groups such as a methyl group, an ethyl group, apropyl group, a butyl group, a pentyl group, a cyclopentyl group, ahexyl group, a cyclohexyl group, a 2-cyclohexyl-ethyl group, an octylgroup and a dodecyl group; unsaturated hydrocarbon bond-containinggroups such as a vinyl group, an ethynyl group, an allyl group and a2-cyclohexenyl-ethyl group; aromatic hydrocarbon groups such as a phenylgroup, a benzyl group and a phenethyl group; fluorine atom-containinggroups, e.g., fluorine-containing alkyl group such as a3,3,3-trifluoro-n-propyl group and fluorine-containing ether groups suchas a CF₃CF₂CF₂OCH₂CH₂CH₂— group; and hydrocarbon groups substituted withpolar substituent(s), such as an aminopropyl group, anaminoethylaminopropyl group, an aminoethylaminophenethyl group, anacryloxypropyl group and a cyanopropyl group and the like. In thisconnection, in the general formula (13), two or more hydrogen atoms arenot connected to the same silicon atom at the same time. Specificexamples of the silicon atom-containing group represented by the generalformula (13) include a trimethylsiloxy group (Me₃Si—), adimethylphenylsiloxy group (Me₂PhSiO—), a diphenylmethylsiloxy group, aphenethyldimethylsiloxy group, a dimethyl-n-hexylsiloxy group, adimetylcyclohexylsiloxy group, a dimethyloctylsiloxy group,(CH₃)₃SiO[Si(CH₃)₂O]_(k)— (k=1 to 9), a2-phenyl-2,4,4,4-tetramethyldisiloxy group (OSiPhMeOSiMe₃),4,4-diphenyl-2,2,4-trimethyldisiloxy (OSiMe₂OSiMePh₂),2,4-diphenyl-2,4,4-trimethyldisiloxy (OSiPhMeOSiPhMe₂), avinyldimethylsiloxy group, a 3-glycidylpropyldimethylsiloxy group, a3-aminopropyldimethylsiloxy group (H₂NCH₂CH₂CH₂Me₂SiO—),H₂NCH₂CH₂CH₂Me(HO)SiO—, a 3-(2-aminoethylamino)propyldimethylsiloxygroup (H₂NCH₂CH₂NHCH₂CH₂CH₂Me₂SiO—), H₂NCH₂CH₂NHCH₂CH₂CH₂Me(HO)SiO—, andthe like.

In the general formula (14), Ra is a divalent hydrocarbon group having 1to 10 carbon atoms and the number of the carbon atoms is preferably inthe range of 2 to 6, particularly preferably 2 or 3. Specific examplesof Ra include alkylene groups such as —CH₂CH₂—, —CH₂CH₂CH₂—, and—(CH2)_(m)— (m=4 to 10).

The definitions of R₆, R₇ and R₈ in the general formula (14) are thesame as those of R₆, R₇ and R₈ in the general formula (13),respectively. Moreover, the definitions of R₉ and R₁₀ are the same asthose of R₆ and R₇. n′ is 0 or an integer of the range of 1 to 9 but ispreferably 0 or an integer of the range of 1 to 5, particularlypreferably 0, 1 or 2.

In the invention, cage silsesquioxanes and/or partially cleavedstructures thereof having a wide range of structures including thegeneral formula (A) and/or the general formula (B) as representative(s)are used. In the general formulae (A) and (B), a plurality of R, X, Yand Z in one molecule may be the same or different from each other.

Among the compounds represented by the general formulae (A) and (B), asa group of the compounds exhibiting particularly excellent effects ofboth of a moldability (or melt flowability)-enhancing effect and a flameresistance-enhancing effect of the polyphenylene ether-based resincomposition, there may be mentioned a group of the compounds having aratio of “the number of R, X, Y and Z which are aromatic hydrocarbongroups” to “the number of all of R, X, Y and Z” of preferably 93% orless, more preferably 90% or less, particularly preferably 80% or less,further preferably 70% or less. In this connection, in the both cases of“the number of all of R, X, Y and Z” and “the number of R, X, Y and Zwhich are aromatic hydrocarbon groups”, each of the same groups in allof R, X, Y and Z is to be counted as one substituent. In the compoundsrepresented by the general formulae (A) and (B), particularly thecompounds represented by the general formula (A), when the ratio of “thenumber of R, X, Y and Z which are aromatic hydrocarbon groups” to “thenumber of all of R, X, Y and Z” becomes more than the above ratio, theflowability-enhancing effect and flame resistance-enhancing effect ofthe polyphenylene ether-based resin composition tend to decrease.Therefore, in the compounds represented by the general formulae (A) and(B), particularly the compounds represented by the general formula (A),the ratio of “the number of R, X, Y and Z which are aromatic hydrocarbongroups” is preferably within the above range. In this connection, thearomatic hydrocarbon group herein means an aromatic hydrocarbon groupselected from aryl groups and aralkyl groups. Since a polyphenyleneether resin is a polymer containing aromatic nuclei as mainconstituents, such effects of the aromatic hydrocarbon group having asimilar structure to the polymer structure are entirely unexpectableeffects based on the hitherto known facts and are revealed for the firsttime by the precise investigation of the inventors.

Among the compounds represented by the general formulae (A) and (B), asanother group of the compounds exhibiting particularly excellent effectsof both of a moldability (or melt flowability)-enhancing effect and aflame resistance-enhancing effect of the polyphenylene ether-based resincomposition, there may be mentioned a group of the compounds wherein atleast one of R, X, Y and Z in the general formula (A) and/or the generalformula (B) is 1) a group containing an unsaturated hydrocarbon bond or2) a group having a polar group containing a nitrogen atom and/or anoxygen atom. In the case that R, X, Y or Z is composed of two or morekinds of groups, it is sufficient that at least one of the groups is thegroup of above 1) or 2).

Examples of the group containing an unsaturated hydrocarbon bond includeacyclic or cyclic alkenyl and alkynyl groups such as vinyl, propenyl,butenyl, pentenyl, hexenyl, cyclohexenyl, cyclohexenylethyl,norbornenyl, norbornenylethyl, heptenyl, octenyl, nonenyl, decenyl,undecenyl, dodecenyl, styrenyl and styryl groups, or groups containingthese groups. Specific examples of the above group containing anunsaturated hydrocarbon bond include a vinyl group, an allyl group, a2-(3,4-cyclohexenyl)ethyl group, a 3,4-cyclohexenyl group, adimethylvinylsiloxy group, a dimethylallylsiloxy group, a(3-acryloylpropyl)dimethylsiloxy group, a(3-methacryloylpropyl)dimethylsiloxy group, and the like.

Moreover, examples of the group having a polar group containing anitrogen atom and/or an oxygen atom include groups containing an etherbond, an ester bond, a hydroxyl group, a carbonyl group, an aldehydegroup, an epoxy group (bond), an amino group, an amide group (bond), acyano group, a urea group (bond), an isocyanate group, and the like.Among them, a group containing an amino group or epoxy group isparticularly preferred. Specific examples of the above group containingan amino group include 3-aminopropyl group (H₂NCH₂CH₂CH₂—), a3-aminopropyldimethylsiloxy group (H₂NCH₂CH₂CH₂Me₂SiO—),H₂NCH₂CH₂CH₂Me(HO)SiO—, a 3-(2-aminoethylamino)propyl group(H₂NCH₂CH₂NHCH₂CH₂CH₂—), a 3-(2-aminoethylamino)propyldimethylsiloxygroup (H₂NCH₂CH₂NHCH₂CH₂CH₂Me₂SiO—), H₂NCH₂CH₂NHCH₂CH₂CH₂Me(HO)SiO—, andthe like. Moreover, specific examples of the above group containing anepoxy group include a 3-glycidyloxypropyl group, a3-glycidyloxypropyldimethylsiloxy group, a 2-(3,4-epoxycyclohexyl)ethylgroup, a 2-(3,4-epoxycyclohexyl)ethyldimethylsiloxy group, and the like.

R, X, Y and Z each independently may be selected from various structuresand also, R, X, Y and Z each may be composed of a plurality of groups.

As a result of studies on the structures of cage silsesquioxanes andpartially cleaved structures of the cage silsesquioxanes suitable forthe polyphenylene ether-based resin composition of the invention fromwide and various viewpoints, the inventors have found that, among thecompounds of the general formula (B), a compound (hereinafter,abbreviated as compound (B-0)) wherein a) at least one of a plurality ofX's is a group selected from a hydroxyl group and —OSi(OH)Y″Z″ and b) atleast one of a plurality of X's is 1) a group containing an unsaturatedhydrocarbon bond or 2) a group having a polar group containing at leastone of a nitrogen atom and an oxygen atom as mentioned above, whichexhibits excellent effects in the compounds of the general formulae (A)and (B), provides a practically extremely excellent composition which isexcellent in the low volatility in addition to the meltflowability-enhancing effect and the flame resistance-enhancing effectdescribed in the above. Y″ and Z″ in the above —OSi(OH)Y″Z″ are selectedfrom the group consisting of the same groups as those for X in thegeneral formula (B) and Y″ and Z″ may be the same or different.

In this connection, the case that at least one of a plurality of X's isa group containing an amino group in the above compound (B-0) is morepreferred since it affords a polyphenylene ether-based resin compositionhaving particularly excellent and balanced characteristic properties ofany of a high melt flowability, a high flame resistance, and a lowvolatility. Moreover, the amino group-containing compound (B-0) is acompound on which novel excellent characteristic properties as mentionedabove are confirmed and also is a novel substance hitherto unknown.

As an example of more specific structure of the compound (B-0), thefollowing general formula (B-1) may be mentioned, for example.(RSiO_(3/2))_(l)(RX_(a1)SiO)(Rx_(a2)SiO)(RX_(b)SiO)  (B-1)wherein, in the general formula (B-1), R and l are the same as in thecase of the general formula (B); X_(a1) and X_(a2) are selected from thegroup consisting of the same groups as those for X in the generalformula (B) and X_(a1) and X_(a2) may be connected to each other to forma connected structure represented by the general formula (1-1):

wherein X_(b)is a group selected from a hydroxyl group and —OSi(OH)Y″Z″;Y′, Z′, Y″ and Z″ are selected form a group consisting of the samegroups as those for X in the general formula (B); provided that at leastone of X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ in the same compoundis 1) a group containing an unsaturated hydrocarbon bond or 2) a grouphaving a polar group containing a nitrogen atom and/or an oxygen atomand X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ are the same or differentfrom each other. Moreover, with regard to Y″ and Z″ in the generalformula (B-1), the specific examples thereof will be described below. Y″and Z″ in the general formula (B-0) are also selected from groupsconsisting of the same groups as those for Y″ and Z″ in the generalformula (B-1), respectively.

Among the compounds of the general formula (B-1), the case that at leastone of X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ is a group containing anamino group is more preferred since it affords a polyphenyleneether-based resin composition having particularly excellent and balancedcharacteristic properties of any of a high melt flowability, a highflame resistance, and a low volatility.

Moreover, in the compounds of the general formula (B-1), the partiallycleaved structure of the cage silsesquioxane wherein at least one ofX_(a1), X_(a2), X_(b), Y′, Z′ Y″ and Z″ is a group containing an aminogroup is a compound on which novel excellent characteristic propertiesas mentioned above are confirmed and also is a novel substance hithertounknown.

Examples of the specific structure include the compounds having thefollowing skeletal structures (examples wherein 1=4 in the generalformula (B-1)) but the structure is not limited thereto.

In the above compounds (B-1-a) and (B-1-b), the mutual positions of Y′group and Z′ group, the OH group and R group or —OSi(OH)Y″Z″ group and Rgroup bonded to the same silicon atom may be exchanged each other.Specific examples of Y′ and Y″ in the above compound (B-1-a) and (B-1-b)include lower alkyl groups such as methyl and propyl groups, and aphenyl group. Specific examples of Z′ and Z″ include aliphatic aminogroups such as a —CH₂CH₂CH₂NH₂ group and a —CH₂CH₂CH₂NHCH₂CH₂CH₂NH₂group and aromatic amino groups such as a —CH₂CH₂C₆H₄NH₂ group. In thisconnection, in the case that Z′ is a group containing an amino group, Z″is not necessarily a group containing an amino group. To the contrary,in the case that Z″ is a group containing an amino group, Z′ is notnecessarily a group containing an amino group.

The reason why the compound represented by the general formula (B-1),particularly the compound represented by the general formula (B-1)wherein at least one of Y′, Z′, Y″ and Z″ is a group containing an aminogroup is excellent in the low volatility in addition to the meltflowability-improving effect and flame resistance-improving effect andprovides a practically extremely excellent composition is not clear atthis moment. However, with regard to the low volatility of the compoundrepresented by the general formula (B-1), since the compound representedby the general formula (B-1) contains at least one silanol group, forexample, there is considered a possibility that the silanol groupinhibits the volatility of the compound for some reason.

With regard to the volatility of the compound represented by the generalformula (B-1), when compared with that of the cage silsesquioxane orpartially cleaved structure of the cage silsesquioxane containing asimilar functional group but no silanol group, an initiation temperatureof thermal decomposition or an initiation temperature of sublimation,e.g., a temperature at which a 10% weight decrease is observed onthermogravimetric analysis (TGA) is elevated by several ten ° C. or moreand thus the compound is preferred.

The cage silsesquioxane represented by the general formula (A) or thepartially cleaved structure of the cage silsesquioxane represented bythe general formula (B) for use in the invention has both a feature thatthe polyphenylene ether-based resin composition results in a small molddeposit at melt molding as shown in Examples. In the case of thecompound represented by the general formula (B-1), the low volatility isfurther improved with still having a high melt flowability and a highflame resistance. Therefore, in the melt molding of the polyphenyleneether-based resin composition of the invention using the compoundrepresented by the general formula (B-1), it is possible to carry out ahighly precise molding with a particularly small mold deposit. Such afeature of the compound represented by the general formula (B-1),particularly the compound represented by the general formula (B-1)wherein at least one of Y′, Z′, Y″ and Z″ is a group containing an aminogroup is extremely important for the production of a precise moldedarticle.

With regard to the compound represented by the general formula (B-1), itis also an important feature that the compound having a structurecontaining a variety of functional groups suitable for intended use canbe synthesized extremely easily. Namely, the compound represented by thegeneral formula (B-1) is easily synthesized by the reaction of atrisilanol compound wherein k is 3 and X is OH in the general formula(B) with a Y′Z′SiD₂ (D=Cl, a lower alkoxyl group such as —OMe or —OEt,or the like) type compound and/or a Y″Z″SiD₂ (D=Cl, a lower alkoxylgroup such as —OMe or —OEt, or the like) type compound.

Synthetic examples thereof will be illustrated in the following but arenot limited thereto.

In the above compounds (B-1-1) and (B-1-2), the mutual positions of Y′group and Z′ group, the OH group and R group or —OSi(OH)Y″Z″ group and Rgroup bonded to the same silicon atom may be exchanged for each other.

In this connection, a compound having a structure wherein the abovegroup in the case that X_(b) in the general formula (B-1) is a hydroxylgroup or the OH group contained in —OSi(OH)Y″Z″ in the case that X_(b)is the group is a chlorine atom or an alkoxyl group is easily hydrolyzedby the action of a minute amount of water or the like present in the airand is converted into the structure of the compound of the generalformula (B-1). Therefore, the above chlorine atom-containing group oralkoxyl group-containing group can be regarded as an equivalent of thecompound of the general formula (B-1) for use in the invention.

The cage silsesquioxane of the invention can be synthesized by themethods described in Brown et al., J. Am. Chem. Soc. 1965, 87, 4313,Feher et al., J. Am. Chem. Soc. 1989, 111, 1741 or Organometallics 1991,10, 2526, and the like. For example, the compound can be obtained ascrystals by reacting cyclohexyltriethoxysilane in water/methyl isobutylketone with adding tetramethylammonium hydroxide as a catalyst.Moreover, trisilanol compounds and disilanol compounds represented bythe general formulae (8) (X═OH), (10) (X═OH) and (11) (X═OH) are formedat the production of completely condensed cage silsesquioxane at thesame time or can be also synthesized by partial cleavage of thecompletely condensed cage silsesquioxane with trifluoro acid ortetraethylammonium hydroxide (cf. Feher et al., Chem. Commun., 1998,1279). Furthermore, the compound of the general formula (8) (X═OH) canbe also synthesized directly from a RSiT₃ (T=Cl or an alkoxyl group)type compound.

As a method of introducing a different substituent R′ instead of onlyone R of eight R's in the general formula (4), there is mentioned amethod of reacting the trisilanol compound represented by the generalformula (8) (X═OH) with R′SiCl₃, R′Si(OMe)₃, R′Si(OEt)₃, or the like. Asa specific example of such a synthesis, a partially cleaved structure ofthe cage silsesquioxane represented by the general formula (8) (R=acyclohexyl group, X═OH) is synthesized by the above method, and then thedesired compound can be synthesized by adding 3 equivalents oftriethylamine to a mixture of 1 equivalent of HSiCl₃ and 1 equivalent ofthe partially cleaved structure of the cage silsesquioxane representedby the general formula (8) (R=a cyclohexyl group, X═OH) in atetrahydrofuran solution (e.g., cf. Brown et al., J. Am. Chem. Soc.1965, 87, 4313).

As a specific example of the method for introducing a siliconatom-containing group as X in the partially cleaved structure of thecage silsesquioxane represented by the general formula (B), there maybe, for example, mentioned a method for producing a compound into whicha Me₃SiO— group is introduced as X by adding 3 equivalents oftriethylamine and 3 equivalents of trimethylchlorosilane intetrahydrofuran relative to 1 equivalent of the partially cleavedstructure of the cage silsesquioxane represented by the general formula(8) (R=a cyclohexyl group, X═OH) (e.g., cf. J. Am. Chem. Soc. 1989, 111,1741).

The structural analysis of the cage silsesquioxane of the invention canbe carried out by X-ray structural analysis (Larsson et al., Alkiv Kemi16, 209 (1960)) but simply, identification can be carried out byinfra-red absorption spectroscopy and NMR (e.g., cf. Vogt et al.,Inorga. Chem. 2, 189 (1963)).

The cage silsesquioxane or partially cleaved structure of the cagesilsesquioxane for use in the invention may be used singly or as amixture of two or more of them. Furthermore, the cage silsesquioxane andpartially cleaved structure of the cage silsesquioxane may be used incombination.

Moreover, the cage silsesquioxane, partially cleaved structure of thecage silsesquioxane, or mixture thereof for use in the invention may beused in combination with other organosilicon compounds having the otherstructures. Examples of the organosilicon compounds having the otherstructures in this case include polydimethylsilicone,polydimethyl/methylphenylsilicone, substituted silicone compoundscontaining polar substituents such as amino groups, hydroxyl groups, orthe like, amorphous polymethylsilsesquioxanes, various ladder-typesilsesquioxanes, and the like. At that case, the composition ratio ofthe mixture is not particularly limited but usually, the ratio of thecage silsesquioxane and/or partially cleaved structure thereof to beused in the above mixture is preferably 10% by weight or more, morepreferably 30% by weight or more, particularly preferably 50% by weightor more.

When an amorphous polysilsesquioxane which does not form a cage is usedas an additive for a polyphenylene ether-based resin composition insteadof the cage silsesquioxane or partially cleaved structure of the cagesilsesquioxane represented by the general formulae (A), (B) and (3) to(12) for use in the invention, the effect on the melt flowabilityenhancement and flame resistance enhancement are found to be small.

The content of the cage silsesquioxane represented by the generalformula (A), the partially cleaved structure of the cage silsesquioxanerepresented by the general formula (A), or a mixture thereof in thepolyphenylene ether-based resin composition of the invention ispreferably from 0.1% by weight to 90% by weight. The content to be usedis more preferably in the range of 0.1% by weight to 50% by weight,further preferably in the range of 0.5% by weight to 30% by weight,particularly preferably in the range of 0.5% by weight to 15% by weight.When the amount added is smaller than the above range, the effects onthe melt flowability enhancement and flame resistance enhancement arefound to be small. When it is larger than the above range, physicalproperties such as mechanical strength decrease and thus the case is notpreferable. In the polyphenylene ether-based resin composition of theinvention, as specifically shown in Examples to be described below, thecage silsesquioxane represented by the general formula (A), thepartially cleaved structure of the cage silsesquioxane represented bythe general formula (B), or a mixture thereof exhibits excellent meltflowability-enhancing effect and/or flame resistance-enhancing effecteven when added in an extremely small amount. Therefore, in thiscomposition, different from the cases of using other additives hithertoknown, there is an industrially extremely important advantage that themelt flowability and flame resistance can be improved with hardlyimpairing the high heat resistance and good mechanical properties, whichare original features of a polyphenylene ether resin.

The polyphenylene ether-based resin composition of the invention may befurther incorporated with a cyclic nitrogen compound having a specificstructure as a flame retardant aid. The cyclic nitrogen compound for usein the invention means a compound basically having a triazine skeletonin the molecule and a melamine derivative. Specific examples thereofpreferably include melamine, melem, and mellon which are melaminederivatives. Among them, melem and mellon are preferred in view of thelow volatility. The cyclic nitrogen compound is preferably a finelypowdered one for exhibiting a flame resistance-enhancing effect. Thesize of the finely powdered particles is that finely powdered to anaverage particle size of preferably 30 μm or less, more preferably 0.05to 5 μm.

The content of the above cyclic nitrogen compound in the polyphenyleneether-based resin composition of the invention is preferably in therange of 0.1% by weight to 20% by weight, more preferably in the rangeof 0.2% by weight to 10% by weight. When the amount added is smallerthan the above range, the effect on the flame resistance is found to besmall and when the amount added is larger than the above range, themechanical properties decreases, so that the cases are not preferable.

The polyphenylene ether-based resin composition of the invention may beincorporated with a fluorine resin for enhancing the flame resistance.Examples of the fluorine resin include polymonofluoroethylene,polyvinylidene fluoride, polytrifluoroethylene, polytetrafluoroethylene,a tetrafluoroethylene/hexafluoropropylene copolymer, and the like.Particularly preferred is polytetrafluoroethylene. Moreover, a copolymerof a fluorine-containing monomer constituting the above polymer with acopolymerizable monomer may be used. The amount of the fluorine resin tobe added is not limited unless the melt flowability of the invention isimpaired, but the content in the polyphenylene ether-based resincomposition is preferably from 0.01 to 10% by weight, more preferablyfrom 0.03 to 8% by weight, particularly preferably from 0.05 to 6% byweight. When the content is less than 0.01% by weight, the flameresistance-enhancing effect is found to be small and when it exceed 10%by weight, the moldability and the like decrease, so that the cases arenot preferable.

Furthermore, the polyphenylene ether-based resin composition of theinvention may be combined with various inorganic fillers in an amount ofthe range wherein melt-molding of the composition is possible.Incorporation of the inorganic filler can enhance heat resistance,mechanical strength, flame resistance and the like. Examples of theinorganic filler include fibrous materials such as glass fibers andcarbon fibers, microparticulate silica (fumed silica), particulatesilica, glass beads, glass flakes, talc, diatomaceous earth, mica, andthe like. Furthermore, fumed silica whose surface is modified withvarious organic components may be also used.

In the invention, in addition to the above constituents, within therange wherein the features and effects of the invention are notimpaired, the other additional constituents, for example, anantioxidant, an elastomer (an olefinic copolymer such asethylene/propylene copolymer, ethylene/1-butene copolymer,ethylene/propylene/non-conjugate diene copolymer, ethylene/ethylacrylate copolymer, ethylene/glycidyl methacrylate copolymer,ethylene/vinyl acetate/glycidyl methacrylate copolymer andethylene/propylene-g-maleic anhydride copolymer, or ABS, a polyesterpolyether elastomer, a polyester polyester elastomer, a vinyl aromaticcompound-conjugate diene compound block copolymer, a hydrogenatedproduct of a vinyl aromatic compound-conjugate diene compound blockcopolymer), a plasticizer (an oil, a low-molecular-weight polyethylene,an epoxidized soybean oil, polyethylene glycol, a fatty acid ester,etc.), a flame retardant aid, a weather (light) resistance improver, anagent for nucleation of polyolefin, a slip agent, various colorants, areleasing agent, and the like may be added, if necessary.

The resin composition of the invention can be produced by variousmethods. For example, a melt-kneading method under heating using asingle-screw extruder, a twin-screw extruder, a roll, a kneader, aBrabender Plastograph, a Banbury mixer, or the like may be mentioned butamong them, a melt-kneading method using a twin-screw extruder is mostpreferred. The melt-kneading temperature at that time is notparticularly limited but usually, the temperature may be optionallyselected from 150° C. to 380° C. depending on the purpose.

The resin composition of the invention thus obtained can be molded intomolded articles of various parts by various methods hitherto known, forexample, injection molding, extrusion molding, and blow molding. Thepolyphenylene ether-based resin composition of the invention exhibits ahigh melt flowability with hardly impairing the high heat resistance andexcellent mechanical properties intrinsic to polyphenylene ether resins.Therefore, the polyphenylene ether-based resin composition of theinvention is an industrially useful, novel material which can bemelt-molded industrially extremely advantageously with a highproductivity, the resulting molded article exhibiting extremelyexcellent properties. Namely, the polyphenylene ether-based resincomposition of the invention enables a process for producing apolyphenylene ether-based resin molded article having excellentproperties hitherto not known by a melt-molding process industriallyadvantageously.

The molded articles produced from the polyphenylene ether-based resincomposition of the invention by a melt-molding process are suitable forapplications where flame resistance and heat resistance are particularlyrequired, for example, automobile heat-resistant parts or heat-resistantparts for office equipment. As the automobile heat resistant parts, themolded articles are suitable for an alternator terminal, an alternatorconnector, an IC regulator, a potentiometer base for lightdayer, variousvalves such as exhaust gas valves, various fuel, exhaust gas, and airintake pipes, an air intake nozzle snorkel, an intake manifold, a fuelpump, an engine coolant joint, a carburetor main body, a carburetorspacer, an exhaust gas sensor, a coolant sensor, an oil-temperaturesensor, a brake pad wear sensor, a throttle position sensor, acrankshaft position sensor, an air flow meter, a brake pad abrasionsensor, a thermostat base for air conditioner, a warm-air-flowcontrolling valve, a brush holder for radiator motor, a water pumpimpeller, turbine vanes, wiper motor parts, a distributor, a startingswitch, a starter relay, a wire harness for transmission, a windowwasher nozzle, an air-conditioner panel switch board, a coil for fuelelectromagnetic valve, a fuse connector, a horn terminal, an electricalcomponent-insulating board, a step motor rotor, a brake piston, asolenoid bobbin, an engine oil filter, parts such as an ignition devicecase, a wheel cap, a lamp socket, a lamp housing, a lamp extension, alamp reflector, and the like. Of these, the molded articles are suitablefor a lamp extension and a lamp reflector in view of the balance oflightness, heat resistance, flame resistance and mechanical properties.Moreover, with regard to the heat-resistant parts for office equipment,they are suitable for household and office electric appliance partsincluding air-conditioner parts, typewriter parts and word processorparts as representatives, office computer-related parts,telephone-related parts, facsimile-related parts, copyingmachine-related parts, and the like.

EXAMPLES

The following will describe the mode for carrying out the invention indetail with reference to Examples and Comparative Examples. Theinvention is not limited thereto.

Products of Hybrid Plastics Company were employed as the cagesilsesquioxanes and/or partially cleaved structures of the cagesilsesquioxanes used other than those whose Synthetic Examples weredescribed in Examples and Comparative Examples.

Evaluation of physical properties of the resulting cage silsesquioxanesand partially cleaved structures of the cage silsesquioxanes was carriedout in accordance with the following procedures.

(1) Evaluation of Mold Deposit (MD)

One thousand shots of a test piece having a size of 10×25×0.2 mm weremolded and the degree of MD attachment on the mold surface was evaluatedvisually.

(2) Evaluation of Flame Resistance

As evaluation of flame resistance of Examples 4 to 7 and ComparativeExamples 2 and 3, using five plate-like test pieces having a length of126 mm, a width of 12.6 mm and a thickness of 500 μm, they were broughtinto contact with flame twice, the contact time with flame being 5seconds. The combustion time required for extinction was measured ineach case.

As evaluation of flame resistance of Examples 8 to 18 and 29 to 32 andComparative Examples 4 to 5 and 10 to 11, using five plate-like testpieces having a length of 126 mm, a width of 12.6 mm and a thickness of1/16 inch, evaluation on average combustion time, maximum combustiontime and number of droppings was carried out in accordance with UL-94(U.S.A. Underwriter Laboratory's Standard).

As evaluation of flame resistance of Examples 19 to 28 and ComparativeExamples 6 to 9, using five plate-like test pieces having a length of126 mm, a width of 12.6 mm and a thickness of 1.5 mm, evaluation onaverage combustion time, maximum combustion time and number of droppingswas carried out in accordance with UL-94 (U.S.A. UnderwriterLaboratory's Standard).

(3) Melt Flowability

In accordance with JIS K6730, melt index (MI) of mainly resincomposition at 280° C. and a load of 10 kg was measured to evaluate amelt flow rate (MFR).

(4) Heat Resistance

The glass transition point (Tg) of a film having a length of 27 mm, awidth of 3 mm and a thickness of 200 μm was evaluated using a vibronmfd. by Orientech.

(5) Tensile Strength

A tensile strength of a film having a length of 40 mm, a width of 10 mmand a thickness of 200 μm was evaluated using a tensile tester (model1356) mfd. by AIKOH.

Example 1

Ninety-five percent by weight of poly(2,6-dimethyl-1,4-phenylene)etherdried at 150° C. for 4 hours and having a molecular weight (Mw) of 37100and Mw/Mn of 2.06 and 5% by weight of octaisobutyloctasilsesquioxane (acompound of the general formula (4) wherein R is an isobutyl group) werepremixed and then melt-kneaded in a Laboplastomill (mfd. by Toyo Seiki)set at 300° C. for 10 minutes. The resulting resin composition waspressed on a heating press of maximum 100 kg set at 300° C. for 10minutes and on a cooling press of maximum 100 kg set at 90° C. for 2minutes to obtain a plate-like molded article of 200 μm.

When the resulting molded article was analyzed by ¹H- and ²⁹Si-NMR,peaks characteristic to octaisobutyloctasilsesquioxane (¹H: 1.87 ppm,0.96 ppm, 0.62 ppm, ²⁹Si: −64 ppm) were detected and thus it wasconfirmed that octaisobutyloctasilsesquioxane was not decomposed byheating. Moreover, by fluorescent X-ray (XRF), it was confirmed thatoctaisobutyloctasilsesquioxane was contained in the same amount as theamount charged.

Table 1 shows evaluation results of the resin composition.

Examples 2 and 3 and Comparative Example 1

In Examples 2 and 3, resin compositions were obtained in a similarmanner to Example 1 with the exception that the kind and amount added ofthe cage silsesquioxane compound were changed, and then evaluated. Thestructures of the compounds were shown in Table 2. With regard toComparative Example 1, a sole polyphenylene ether resin compositionwithout a cage silicon compound was evaluated.

Table 1 shows evaluation results.

TABLE 1 Tensile Amount MFR Tg strength Example No. Additive added (g/10min) (° C.) (Kg/mm²) Example 1 Compound A 5% by 4.4 211 6.1 weightExample 2 Compound B* 5% by 6.8 212 6.2 weight Example 3 Compound B* 2%by 4.3 215 6.0 weight Comparative No addition 2.4 217 6.3 Example 1 *Amixture of cage silsesquioxanes having 8 to 12 silicone atoms

TABLE 2 Compound A Compound B Structure

From Table 1, it is found that the polyphenylene ether-based resincompositions to which a cage silsesquioxane compound is incorporatedimprove melt flowability to a large extent while hardly decreasing heatresistance and tensile strength.

Examples 4 to 7 and Comparative Example 2

In Example 4, a resin composition was obtained in a similar manner toExample 1 with the exception that the amount of Compound A added waschanged and a test piece having a length of 126 mm, a width of 12.6 mmand a thickness of 500 μm was prepared.

In Examples 5 and 7, resin compositions were obtained in a similarmanner to Example 4 with the exception that the kind and amount added ofthe cage silsesquioxane compound were changed, and then evaluated. Thestructures of the compounds are shown in Table 4.

With regard to Comparative Example 2, a sole polyphenylene ether resincomposition using no cage silicon compound was evaluated.

Comparative Example 3

To a glass vessel were added 100 parts of methyltriethoxysilane and 80parts of toluene, and 50 parts of 1% by weight hydrochloric acid aqueoussolution were added gradually thereto with stirring to effect hydrolysisof the silane. After completion of the addition, the liquid wasseparated to take out an organic phase. After washing with water, thesolvent, toluene was removed to obtain polymethylsilsesquioxanecontaining a silanol group. The molecular weight of the resultingpolymethylsilsesquioxane was found to be about 5000 (measured on GPC, interms of polystyrene), and the content of the silanol group was about 5mol % (NMR spectrum). A resin composition was obtained in a similarmanner to Example 4 with the exception that the silicon compound wasused, and then evaluated.

Table 3 shows evaluation results.

TABLE 3 Average com- bus- Amount tion Maximum Number of Example addedtime combustion droppings No. Additive (%) (sec) time (sec) (number)Example 4 Compound A 10% by 4.7 9.7 0/10 weight Example 5 Compound A  5%by 3.7 14.0 0/10 weight Example 6 Compound C 10% by 5.6 10.5 0/10 weightExample 7 Compound D 10% by 5.9 11.3 0/10 weight Compara. No addition8.6 21.3 0/10 Example 2 Compara. Polymethylsil 10% by 7.9 15.8 2/10Example 3 sesquioxane weight

TABLE 4 Compound A Compound C Compound D Structure

From Table 3, it is found that the polyphenylene ether-based resincompositions to which a cage silsesquioxane compound is added areexcellent in flame resistance.

Example 8

Evaluation was further carried out with changing the process forproducing compositions, the method for preparing test pieces, and thekind and amount to be added of the cage silsesquioxane or partiallycleaved structure thereof.

Ninety-five percent by weight of poly(2,6-dimethyl-1,4-phenylene)etherdried at 150° C. for 4 hours and having a molecular weight (Mw) of 37100and Mw/Mn of 2.06 and 5% by weight ofheptaisobutyl-heptasilsesquioxane-trisilanol (a compound of the generalformula (8) wherein R is an isobutyl group and X is a hydroxy group)were premixed, then charged into a twin-screw extruder (mfd. byTechnobell, ZSW-15) set at 280° C., and melt-kneaded to obtain apolyphenylene ether-based resin composition. Pellets of the resultingresin composition were molded at an injection rate of 50 mm/sec using aninjection molding machine (FANUC FAS-15A) set at a mold temperature of90° C. with setting cylinder temperatures at 290/290/290/290° C. Table 5shows evaluation results of the resulting composition.

Examples 9 to 15

Resin compositions were obtained in a similar manner to Example 8 withthe exception that the kind and amount added of the cage silsesquioxaneor partially cleaved structure of the cage silsesquioxane were changed,and were evaluated. The results were shown in Table 5 and the structurein Table 6.

Example 16

In a three-neck glass flask fitted with a reflux condenser and adropping funnel, 21 parts by weight ofheptaisobutyl-heptasilsesquioxane-trisilanol (a compound of the generalformula (8) wherein R is iBu and X is OH) were dissolved in 20 parts byweight of THF and 100 parts by weight of ethanol, and a solution of 6parts by weight of 3-aminopropyldiethoxymethylsilane dissolved in 20parts by weight of ethanol was added dropwise thereto to effecthydrolysis. After completion of the addition, the mixture was heated to60° C. and stirred for 6 hours, and then the solvents, THF and ethanolwere removed by evaporation to obtain the desired product (Compound M).When the resulting partially cleaved structure of the cagesilsesquioxane was analyzed by ¹H- and ²⁹Si-NMR, characteristic peaks(¹H: 0.09 ppm, 0.55 ppm, 0.95 ppm, 1.48 ppm, 1.84 ppm, 2.65 ppm, ²⁹Si:−18.23 ppm, −58.59 ppm, −66.08 ppm, −67.53 ppm, −67.99 ppm) wereobtained. Moreover, the resulting partially cleaved structure of thecage silsesquioxane was mixed with NBA and glycerol and the mixture wasmeasured on FAB-MS (Positive) to result in m/z=891 [M+H]⁺. A resincomposition was obtained in a similar manner to Example 8 with theexception that the partially cleaved structure of the cagesilsesquioxane was used, and was evaluated. Table 6 shows evaluationresults.

Example 17

In a three-neck glass flask fitted with a reflux condenser and adropping funnel, 21 parts by weight ofheptaisobutyl-heptasilsesquioxane-trisilanol (a compound of the generalformula (8) wherein R is iBu and X is OH) were dissolved in 20 parts byweight of THF and 100 parts by weight of ethanol, and a solution of 6parts by weight of 2-ethyl(3-aminopropyl)dimethoxymethylsilane dissolvedin 20 parts by weight of ethanol was added dropwise thereto to effecthydrolysis. After completion of the addition, the mixture was heated to60° C. and stirred for 6 hours, and then the solvents, THF and ethanolwere removed by evaporation to obtain the desired product (Compound N).When the resulting partially cleaved structure of the cagesilsesquioxane was analyzed by ¹H- and ²⁹Si-NMR, characteristic peaks(¹H: 0.07 ppm, 0.58 ppm, 0.94 ppm, 1.56 ppm, 1.84 ppm, 2.63 ppm, 2.82ppm, ²⁹Si: −19.93 ppm, −59.30 ppm, −66.31 ppm, −67.10 ppm, −67.89 ppm)were obtained. Moreover, the resulting partially cleaved structure ofthe cage silsesquioxane was mixed with NBA and glycerol, and the mixturewas measured on FAB-MS (Positive) to result in m/z=934 [M+H]⁺.

A resin composition was obtained in a similar manner to Example 8 withthe exception that the partially cleaved structure of the cagesilsesquioxane was used, and was evaluated. Table 6 shows evaluationresults.

Example 18

Evaluation was carried out using Compound A as an additive and melem.

Ninety-five percent by weight of poly(2,6-dimethyl-1,4-phenylene)etherdried at 150° C. for 4 hours and having a molecular weight (Mw) of 37100and Mw/Mn of 2.06, 2.5% by weight of octaisobutyl-octasilsesquioxane(Compound A), and 2.5% by weight of melem were premixed, then chargedinto a twin-screw extruder (mfd. by Techno Bell, ZSW-15) set at 280° C.,and melt-kneaded to obtain a polyphenylene ether-based resincomposition. Pellets of the resulting resin composition were molded atan injection rate of 50 mm/sec using an injection molding machine (FANUCFAS-15A) set at a mold temperature of 90° C. with setting cylindertemperatures at 290/290/290/290° C. Table 5 shows evaluation results ofthe resulting composition.

Comparative Example 4

A sole polyphenylene ether-based resin composition was obtained in asimilar manner to Example 8 with the exception that no cage siliconcompound was used, and evaluation was carried out. Table 5 shows theresults.

Comparative Example 5

A resin composition was obtained in a similar manner to Example 8 withthe exception that amorphous polymethylsilsesquioxane obtained inComparative Example 3 was used, and evaluation was carried out. Table 5shows the results.

TABLE 5 Flame-resistant test result (UL-94, 1/16′) Amount AverageMaximum Number of added MD combustion combustion droppings MFR ExampleNo. Additive (%) evaluation time (sec) time (sec) (n/10) (g/10 min)Example 8 Compound E   5% by weight ∘ 3.4 8.0 0/10 8.9 Example 9Compound F   5% by weight ∘ 3.1 7.3 0/10 9.8 Example 10 Compound G   5%by weight ∘ 2.1 5.1 0/10 10.4 Example 11 Compound H 2.5% by weight ∘ 1.23.0 0/10 7.8 Example 12 Compound I   5% by weight ∘ 4.1 9.7 0/10 9.8Example 13 Compound J   5% by weight ∘ 3.6 6.4 0/10 9.1 Example 14Compound A   5% by weight ∘ 4.2 7.8 0/10 9.0 Example 15 Compound L   5%by weight ∘ 5.1 11 0/10 9.7 Example 16 Compound M   5% by weight ∘ 3.15.4 0/10 10.2 Example 17 Compound N   5% by weight ∘ 2.2 4.7 0/10 13.8Example 18 Compound A 2.5% by weight ∘ 2.5 4.2 0/10 7.8 Melem 2.5% byweight Comparative No addition ∘ 6.6 25 0/10 5.6 Example 4 ComparativePolymethylsilsesquioxane  10% by weight ∘ 7.6 22 2/10 4.5 Example 5

TABLE 6 Compound E Compound F Structure

Compound H Compound I Structure

Compound A Compound L Structure

Compound N Structure

Compound G Structure

Compound J Structure

Compound M Structure

From Table 5, it is found that in the cage silsesquioxanes and/or thepartially cleaved structure of the cage silsesquioxanes, a systemincorporated with a group containing an unsaturated hydrocarbon bond ora group having a polar group containing at least one of a nitrogen atomand an oxygen atom and a cyclic nitrogen compound results in a smallmold deposit and is more preferable in view of moldability and flameresistance.

Example 19

Ninety-five grams of poly(2,6-dimethyl-1,4-phenylene)ether dried at 150°C. for 4 hours and having a molecular weight (Mw) of 37100 and Mw/Mn of2.06 and 5 g of heptaisobutyl-3-aminopropyl-octasilsesquioxane (CompoundG) were premixed and the mixture was then charged into a Laboplastomill(mfd. by Toyo Seiki) set at 260° C. and melt-kneaded at 80 revolutionsfor 10 minutes to obtain a polyphenylene ether-based resin composition.A block of the resulting resin composition was subjected to pressmolding at 260° C. using a mold having a thickness of 1.5 mm. Table 7shows evaluation results of the resulting composition.

Examples 20 and 21

Evaluation was carried out in a similar manner to Example 19 with theexception that the kind of the cage silsesquioxane was changed (CompoundM). Table 7 shows evaluation results.

Example 22

In a three-neck glass flask fitted with a reflux condenser and adropping funnel, 21 parts by weight ofheptaisobutyl-heptasilsesquioxane-trisilanol (Compound E) were dissolvedin 20 parts by weight of THF and 100 parts by weight of ethanol, and asolution of 12 parts by weight of 3-aminopropyldiethoxymethylsilanedissolved in 20 parts by weight of ethanol was added dropwise thereto toeffect hydrolysis. After completion of the addition, the mixture washeated to 60° C. and stirred for 6 hours, and then the solvents, THF andethanol were removed by evaporation to obtain the desired product(Compound 0). When the resulting partially cleaved structure of the cagesilsesquioxane was analyzed by ¹H- and ²⁹Si-NMR, characteristic peaks(¹H: 0.10 ppm, 0.58 ppm, 0.94 ppm, 1.46 ppm, 1.64 ppm, 1.80 ppm, 2.64ppm, 3.48 ppm, ²⁹Si: −10.98 ppm, −18.06 ppm, −66.00 ppm, −67.03 ppm,−67.91 ppm) were obtained. Moreover, the resulting partially cleavedstructure of the cage silsesquioxane was mixed with NBA and glycerol andthe mixture was measured on FAB-MS (Positive) to result in m/z=1009[M+H]⁺.

A resin composition was obtained in a similar manner to Example 19 withthe exception that the partially cleaved structure of the cagesilsesquioxane was used, and was evaluated. Evaluation results are shownin Table 7 and structure in Table 8.

Example 23

In a three-neck glass flask fitted with a reflux condenser and adropping funnel, 21 parts by weight ofheptaisooctyl-heptasilsesquioxane-trisilanol (a compound of the generalformula (8) wherein R is iOct and X is OH) were dissolved in 20 parts byweight of THF and 100 parts by weight of ethanol, and a solution of 6parts by weight of 2-ethyl(3-aminopropyl)diethoxymethylsilane dissolvedin 20 parts by weight of ethanol was added dropwise thereto to effecthydrolysis. After completion of the addition, the mixture was heated to60° C. and stirred for 6 hours, and then the solvents, THF and ethanolwere removed by evaporation to obtain the desired product (Compound P).When the resulting cage silsesquioxane was analyzed by ¹H- and ²⁹Si-NMR,characteristic peaks (¹H: 0.58 ppm, 0.77 ppm, 0.89 ppm, 1.00 ppm, 1.14ppm, 1.30 ppm, 1.80 ppm, 2.02 ppm, 2.66 ppm, 2.80 ppm, ²⁹Si: −67.25 ppm,−67.43 ppm, −67.56 ppm) were obtained. Moreover, the resulting partiallycleaved structure of the cage silsesquioxane was mixed with NBA andglycerol and the mixture was measured on FAB-MS (Positive) to result inm/z=1311 [M+H]⁺.

A resin composition was obtained in a similar manner to Example 19 withthe exception that the cage silsesquioxane was used, and was evaluated.Evaluation results are shown in Table 7 and structure in Table 8.

Example 24

Evaluation was carried out in a similar manner to Example 19 with theexception that the kind of the cage silsesquioxane was changed (CompoundQ). Evaluation results are shown in Table 7 and structure in Table 8.

Example 25

In a three-neck glass flask fitted with a reflux condenser and adropping funnel, 20 parts by weight ofheptaisobutyl-heptasilsesquioxane-trisilanol (Compound E) were dissolvedin 70 parts by weight of THF, and 8 parts by weight of triethylamine wasadded. Then, 17 parts by weight of diphenylmethylchlorosilane were addeddropwise thereto to effect a reaction. After completion of the addition,the mixture was stirred for 6 hours. After filtration of theprecipitated salt through a filter, the solvent, THF was removed byevaporation to obtain the desired product (Compound R). When theresulting partially cleaved structure of the cage silsesquioxane wasanalyzed by ¹H- and ²⁹Si-NMR, characteristic peaks (¹H: 0.41 ppm, 0.48ppm, 0.87 ppm, 0.94 ppm, 1.84 ppm, 7.28 ppm, 7.49 ppm, ²⁹Si: −10.98 ppm,−10.43 ppm, −66.36 ppm) were obtained.

A resin composition was obtained in a similar manner to Example 19 withthe exception that the partially cleaved structure of the cagesilsesquioxanes was used, and was evaluated. Evaluation results areshown in Table 7 and structure in Table 8.

Example 26

In a three-neck glass flask fitted with a reflux condenser and adropping funnel, 10 parts by weight ofheptaphenyl-heptasilsesquioxane-trisilanol (a compound of the generalformula (8) wherein R is Ph and X is OH) were dissolved in 40 parts byweight of THF and 40 parts by weight of ethanol, and 1 part by weight oftriethylamine was added. Then, a solution of 2 parts by weight ofisobutyltrimethoxysilane dissolved in 20 parts by weight of ethanol wereadded dropwise thereto to effect hydrolysis. After completion of theaddition, the mixture was stirred for 6 hours, and then the solvents,THF and ethanol were removed by evaporation to obtain the desiredproduct (Compound S). When the resulting cage silsesquioxane wasanalyzed by ¹H- and ²⁹Si-NMR, characteristic peaks (¹H: 0.58 ppm, 0.89ppm, 1.80 ppm, 7.32 ppm, ²⁹Si: −70.14 ppm, −75.82 ppm, −78.01 ppm) wereobtained.

A resin composition was obtained in a similar manner to Example 19 withthe exception that the cage silsesquioxane was used, and was evaluated.Evaluation results are shown in Table 7 and structure in Table 8.

Example 27

In a three-neck glass flask fitted with a reflux condenser and adropping funnel, 10 parts by weight ofheptaphenyl-heptasilsesquioxane-trisilanol (a compound of the generalformula (8) wherein R is Ph and X is OH) were dissolved in 70 parts byweight of THF, and 4 parts by weight of triethylamine was added. Then,3.5 parts by weight of trimethylchlorosilane were added dropwise theretoto effect a reaction. After completion of the addition, the mixture wasstirred for 6 hours. After filtration of the precipitated salt through afilter, the solvent, THF was removed by evaporation to obtain thedesired product (Compound T). When the resulting partially cleavedstructure of the cage silsesquioxane was analyzed by ¹H- and ²⁹Si-NMR,characteristic peaks (¹H: 0.26 ppm, 6.86 ppm, 7.24 ppm, ²⁹Si: 11.71 ppm,−77.19 ppm) were obtained.

A resin composition was obtained in a similar manner to Example 19 withthe exception that the partially cleaved structure of the cagesilsesquioxanes was used, and was evaluated. Evaluation results areshown in Table 7 and structure in Table 8.

Example 28

In a three-neck glass flask fitted with a reflux condenser and adropping funnel, 10 parts by weight ofheptaphenyl-heptasilsesquioxane-trisilanol (a compound of the generalformula (8) wherein R is Ph and X is OH) was dissolved in 70 parts byweight of THF, and 4 parts by weight of triethylamine were added. Then,5.5 parts by weight of dimethylphenylchlorosilane were added dropwisethereto to effect a reaction. After completion of the addition, themixture was stirred for 6 hours. After filtration of the precipitatedsalt through a filter, the solvent, THF was removed by evaporation toobtain the desired product (Compound U). When the resulting partiallycleaved structure of the cage silsesquioxane was analyzed by ¹H- and²⁹Si-NMR, characteristic peaks (¹H: 0.04 ppm, 6.80 ppm, 7.05 ppm, ²⁹Si:0.93 ppm, −78.22 ppm) were obtained.

A resin composition was obtained in a similar manner to Example 19 withthe exception that the partially cleaved structure of the cagesilsesquioxane was used, and was evaluated. Evaluation results are shownin Table 7 and structure in Table 8.

Comparative Example 6

A sole polyphenylene ether-based resin composition was obtained in asimilar manner to Example 19 with the exception that no cagesilsesquioxane was used, and evaluation was carried out. Table 7 showsevaluation results.

Comparative Example 7

Evaluation was carried out in a similar manner to Example 19 with theexception that dimethylsiloxane (Shin-Etsu Chemical Co., Ltd KF-96, 20cst) was used, and evaluation was carried out. Table 7 shows evaluationresults.

Comparative Example 8

Evaluation was carried out in a similar manner to Example 19 with theexception that aminomethylsilicone (Shin-Etsu Chemical Co., Ltd KF-858)was used, and evaluation was carried out. Table 7 shows evaluationresults.

Comparative Example 9

To a glass vessel were added 100 parts of phenyltrichlorosilane and 80parts of toluene. With stirring, 50 parts of 1% by weight hydrochloricacid aqueous solution were gradually added thereto to effect hydrolysisof the silane. After completion of the addition, liquid separation wascarried out to remove an organic phase. After washing with water, thesolvent, toluene was removed by evaporation to obtainpolyphenylsilsesquioxane containing a silanol group. The molecularweight of the resulting polyphenylsilsesquioxane was found to be about2000 (measured on GPC, in terms of polystyrene), and the content of thesilanol group was about 10 mol % (NMR spectrum). A resin composition wasobtained in a similar manner to Example 19 with the exception that thesilicon compound was used, and was evaluated. Table 7 shows evaluationresults.

TABLE 7 Flame-resistant test result (UL-94, 1.5 mm) Average MaximumNumber of MFR Example Amount added combustion combustion droppings (g/No. Additive (%) time (sec) time (sec) (n/10) 10 min) Example 19Compound G 5% by weight 3.1 7.4 0/10 6.2 Example 20 Compound H 5% byweight 3.8 8.2 0/10 10.3 Example 21 Compound M 5% by weight 2.6 5.0 0/105.5 Example 22 Compound O 5% by weight 3.9 9.3 0/10 4.0 Example 23Compound P 5% by weight 4.4 9.0 0/10 6.8 Example 24 Compound Q 5% byweight 4.0 9.2 0/10 4.8 Example 25 Compound R 5% by weight 3.4 6.0 0/104.9 Example 26 Compound S 5% by weight 4.0 9.1 0/10 3.4 Example 27Compound T 5% by weight 3.0 8.5 0/10 3.9 Example 28 Compound U 5% byweight 4.2 8.7 0/10 3.9 Compara. No addition 8.6 27.4 0/10 2.3 Example 6Compara. Dimethylsiloxane 5% by weight 5.4 7.6 0/10 2.4 Example 7(KF-96, 20Cst) Compara. Aminomethylsilicone 5% by weight 4.5 7.5 0/102.2 Example 8 (KF-858) Compara. Phenylsilsesquioxane 5% by weight 8.914.9 0/10 2.0 Example 9

TABLE 6 Compound G Compound H Structure

Compound O Compound P Structure

Compound R Compound S Structure

Compound U Structure

Compound M Structure

Compound Q Structure

Compound T

From Table 7, it is found that the cage silsesquioxanes and/or thepartially cleaved structures of the cage silsesquioxanes have anenhanced moldability as compared with silicone oils. In addition, in thecase that the ratio of the group having a polar group containing anitrogen atom and/or an oxygen atom or the aromatic hydrocarbon group inR, X, Y, and Z of the cage silsesquioxanes and/or the partially cleavedstructures of the cage silsesquioxanes is within 93%, the compositionsare found to be excellent in moldability and flame resistance.

Example 29

Ninety percent by weight of poly(2,6-dimethyl-1,4-phenylene)ether driedat 150° C. for 4 hours and having a molecular weight (Mw) of 37100 andMw/Mn of 2.06, 10 parts by weight of polystyrene (mfd. by Asahi ChemicalCo., Ltd, GPPS 685) and 10% by weight of octaisobutyl-octasilsesquioxane[Compound A] were premixed, then charged into a twin-screw extruder(mfd. by Techno Bell, ZSW-15) set at 270° C., and melt-kneaded to obtaina polyphenylene ether-based resin composition. Pellets of the resultingresin composition were molded at an injection rate of 50 mm/sec using aninjection molding machine (FANUC FAS-15A) set at a mold temperature of90° C. with setting cylinder temperatures at 290/290/290/290° C. Table 9shows evaluation results of the resulting composition.

Examples 30 to 32

Resin compositions were obtained in a similar manner to Example 29 withthe exception that the kind and amount added of the cage silsesquioxaneor partially cleaved structure of the cage silsesquioxane were changed,and were evaluated. The results were shown in Table 9 and the structurein Table 10.

Comparative Example 10

A sole polyphenylene ether-based resin composition was obtained in asimilar manner to Example 29 with the exception that no cage siliconcompound was used, and evaluation was carried out. Table 9 shows theresults.

Comparative Example 11

A resin composition was obtained in a similar manner to Example 29 withthe exception that amorphous polymethylsilsesquioxane obtained inComparative Example 3 was used, and evaluation was carried out. Table 9shows the results.

TABLE 9 Flame-resistant test result (UL-94, 1/16′) Amount AverageMaximum Number of added MD combustion combustion droppings Example No.Additive (%) evaluation time (sec) time (sec) (n/10) Example 29 CompoundA 10% by ∘ 5.2 10.2 0/10 weight Example 30 Compound J 10% by ∘ 4.3 8.30/10 weight Example 31 Compound G 10% by ∘ 2.7 6.2 0/10 weight Example32 Compound H 10% by ∘ 2.5 5.6 0/10 weight Compara. No addition ∘ 12.630 0/10 Example 10 Compara. Polymethylsilsesquioxane 10% by ∘ 10.3 292/10 Example 11 weight

TABLE 10 Compound A Compound J Structure

Compound H Structure

Compound G Structure

From Table 9, also in the case of polymer alloys of polyphenyleneether-styrene, the cage silsesquioxanes and/or the partially cleavedstructures of the cage silsesquioxanes are excellent for moldability andflame resistance.

As is apparent from Tables 1 to 10, the polyphenylene ether-based resincompositions to which a specific cage silsesquioxane or partiallycleaved structure of the cage silsesquioxane of the invention isincorporated are excellent in flame resistance.

While the invention has been described in detail and with reference tospecific examples thereof, it will be apparent to one skilled in the artthat various changes and modifications can be made therein withoutdeparting from the spirit and scope thereof.

The present application is based on Japanese Patent Application No.2001-015237 filed on Jan. 24, 2001 and Japanese Patent Application No.2001-289244 filed on Sep. 21, 2001, the contents thereof beingincorporated herein by reference.

INDUSTRIAL APPLICABILITY

According to the present invention, the incorporation of a cagesilsesquioxane and/or partially cleaved structure of the cagesilsesquioxane to a polyphenylene ether-based resin composition affordsa polyphenylene ether-based resin composition which is excellent in heatresistance, mechanical properties, moldability and flame resistance andalso results in a small mold deposit. These are industrially useful.

1. A polyphenylene ether-based resin composition comprising apolyphenylene ether-based resin and at least one member selected fromthe group consisting of a cage silsesquioxane and a partially cleavedstructure of a cage silsesquioxane; wherein the cage silsesquioxane is acompound represented by the general formula (A) and the partiallycleaved structure of the cage silsesquioxane is a compound representedby the general formula (B):[RSiO_(3/2)]_(n)  (A)(RSiO_(3/2))_(l)(RXSiO)_(k)  (B) wherein, in the general formulae (A)and (B), R is selected from a hydrogen atom, an alkoxyl group having 1to 6 carbon atoms, an aryloxy group, a substituted or unsubstitutedhydrocarbon group having 1 to 20 carbon atoms, and a siliconatom-containing group having 1 to 10 silicon atoms, and a plurality ofR's may be the same or different; in the general formula (B), X is agroup selected from OR₁ (R₁ is a hydrogen atom, an alkyl group, an arylgroup, a quaternary ammonium radical), halogen atom and groups definedin the above R, and a plurality of X's may be the same or different or aplurality of X's in (RXSiO)_(k) may be connected to each other to form aconnected structure; and n is an integer of 6 to 14, l is an integer of2 to 12, and k is 2 or 3; and wherein the connected structure in thegeneral formula (B) is a connected structure represented by the generalformula (1):

wherein Y and Z are selected from the group consisting of the samegroups as those for X, and Y and Z may be the same or different.
 2. Apolyphenylene ether-based resin composition comprising a polyphenyleneether-based resin and at least one member selected from the groupconsisting of a cage silsesquioxane and a partially cleaved structure ofa cage silsesquioxane; wherein the cage silsesquioxane is a compoundrepresented by the general formula (A) and the partially cleavedstructure of the cage silsesquioxane is a compound represented by thegeneral formula (B):[RSiO_(3/2)]_(n)  (A)(RSiO_(3/2))_(l)(RXSiO)_(k)  (B) wherein, in the general formulae (A)and (B), R is selected from a hydrogen atom, an alkoxyl group having 1to 6 carbon atoms, an aryloxy group, a substituted or unsubstitutedhydrocarbon group having 1 to 20 carbon atoms, and a siliconatom-containing group having 1 to 10 silicon atoms, and a plurality ofR's may be the same or different; in the general formula (B), X is agroup selected from OR₁ (R₁ is a hydrogen atom, an alkyl group, an arylgroup, a quaternary ammonium radical), halogen atom and groups definedin the above R, and a plurality of X's may be the same or different or aplurality of X's in (RXSiO)_(k) may be connected to each other to form aconnected structure; and n is an integer of 6 to 14, l is an integer of2 to 12, and k is 2 or 3; and wherein at least one member selected fromthe group consisting of R, X, Y, and Z in the general formulae (A) and(B) is 1) a group containing an unsaturated hydrocarbon bond or 2) agroup having a polar group containing at least one member selected fromthe group consisting of a nitrogen atom and an oxygen atom.
 3. Thepolyphenylene ether-based resin composition according to claim 1,wherein the compounds of the general formulae (A) and (B) have a ratioof “the number of R, X, Y, and Z which are aromatic hydrocarbon groups”to “the number of all of R, X, Y, and Z” of 93% or less.
 4. Thepolyphenylene ether-based resin composition according to claim 1,wherein at least one of R, X, Y, and Z in the general formulae (A) and(B) is 1) a group containing an unsaturated hydrocarbon bond or 2) agroup having a polar group containing at least one member selected fromthe group consisting of a nitrogen atom and an oxygen atom.
 5. Apolyphenylene ether-based resin composition comprising a polyphenyleneether-based resin and at least one member selected from the groupconsisting of a cage silsesquioxane and a partially cleaved structure ofa cage silsesquioxane; wherein the cage silsesquioxane is a compoundrepresented by the general formula (A) and the partially cleavedstructure of the cage silsesquioxane is a compound represented by thegeneral formula (B):[RSiO_(3/2)]_(n)  (A)(RSiO_(3/2))_(l)(RXSiO)_(k)  (B) wherein, in the general formulae (A)and (B), R is selected from a hydrogen atom, an alkoxyl group having 1to 6 carbon atoms, an aryloxy group, a substituted or unsubstitutedhydrocarbon group having 1 to 20 carbon atoms, and a siliconatom-containing group having 1 to 10 silicon atoms, and a plurality ofR's may be the same or different; in the general formula (B), X is agroup selected from OR₁ (R₁ is a hydrogen atom, an alkyl group, an arylgroup, a quaternary ammonium radical), halogen atom and groups definedin the above R, and a plurality of X's may be the same or different or aplurality of X's in (RXSiO)_(k) may be connected to each other to form aconnected structure; and n is an integer of 6 to 14, l is an integer of2 to 12, and k is 2 or 3; wherein the compounds of the general formulae(A) and (B) have a ratio of “the number of R, X, Y, and Z which arearomatic hydrocarbon groups” to “the number of all of R, X, Y, and Z” of93% or less; and wherein at least one member selected from the groupconsisting of R, X, Y, and Z in the general formulae (A) and (B) is 1) agroup containing an unsaturated hydrocarbon bond or 2) a group having apolar group containing at least one of a nitrogen atom and an oxygenatom.
 6. The polyphenylene ether-based resin composition according toclaim 3, wherein at least one member selected from the group consistingof R, X, Y, and Z in the general formulae (A) and (B) is 1) a groupcontaining an unsaturated hydrocarbon bond or 2) a group having a polargroup containing at least one of a nitrogen atom and an oxygen atom. 7.A polyphenylene ether-based resin composition comprising a polyphenyleneether-based resin and at least one member selected from the groupconsisting of a cage silsesquioxane and a partially cleaved structure ofa cage silsesquioxane; wherein the cage silsesquioxane is a compoundrepresented by the general formula (A) and the partially cleavedstructure of the cage silsesquioxane is a compound represented by thegeneral formula (B):[RSiO_(3/2)]_(n)  (A)(RSiO_(3/2))_(l)(RXSiO)_(k)  (B) wherein, in the general formulae (A)and (B), R is selected from a hydrogen atom, an alkoxyl group having 1to 6 carbon atoms, an aryloxy group, a substituted or unsubstitutedhydrocarbon group having 1 to 20 carbon atoms, and a siliconatom-containing group having 1 to 10 silicon atoms, and a plurality ofR's may be the same or different; in the general formula (B), X is agroup selected from OR₁ (R₁ is a hydrogen atom, an alkyl group, an arylgroup, a quaternary ammonium radical), halogen atom and groups definedin the above R, and a plurality of X's may be the same or different or aplurality of X's in (RSiO)_(k) may be connected to each other to form aconnected structure; and n is an integer of 6 to 14, l is an integer of2 to 12, and k is 2 or 3; and wherein the compound of the generalformula (B) is a compound represented by the following general formula(B-1):(RSiO_(3/2))_(l)(Rx_(a1)SiO)(Rx_(a2)SiO)(Rx_(b)SiO)  (B-1) wherein, inthe general formula (B-1), R and l are the same as in the case of thegeneral formula (B); X_(a1) and X_(a2) are selected from the groupconsisting of the same groups as those for X in the general formula (B)and X_(a1) and X_(a2) may be connected to each other to form a connectedstructure represented by the general formula (1-1):

wherein X_(b) is a group selected from the group consisting of ahydroxyl group and —OSi(OH)Y″Z″; Y′, Z′, Y″ and Z″ are selected from thegroup consisting of the same groups as those for X in the generalformula (B); provided that at least one of the members selected from thegroup consisting of X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ in the samecompound is 1) a group containing an unsaturated hydrocarbon bond or 2)a group having a polar group containing a nitrogen atom and/or an oxygenatom and X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ may be the same ordifferent from each other.
 8. The polyphenylene ether-based resincomposition according to claim 7 wherein at least one member selectedfrom the group consisting of X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ inthe compound of the general formula (B-1) is a group containing an aminogroup.
 9. A compound represented by the following general formula (B-1):(RSiO_(3/2))_(l)(RX_(a1)SiO)(RX_(a2)SiO)(RX_(b)SiO)  (B-1) wherein, inthe general formula (B-1), R is a member selected from the groupconsisting of a hydrogen atom, an alkoxyl group having 1 to 6 carbonatoms, an aryloxy group, a substituted or unsubstituted hydrocarbongroup having 1 to 20 carbon atoms, and a silicon atom-containing grouphaving 1 to 10 silicon atoms, and a plurality of R's may be the same ordifferent; l is an integer of 2 to 12; X_(a1) and X_(a2) are eachindependently selected from the group consisting of OR₁ (R₁ is ahydrogen atom, an alkyl group, an aryl group, a quaternary ammoniumradical), halogen atom and groups defined in the above R, and aplurality of X_(a1)'s may be the same or different, and a plurality ofX_(a2)'s may be the same or different, and X_(a1) and X_(a2) may beconnected to each other to form a connected structure represented by thegeneral formula (1-1):

wherein X_(b) is a radical selected from the group consisting of ahydroxyl group and —OSi(OH)Y″Z″; Y′, Z′, Y″ and Z″ each is a groupselected from OR₁ (R₁ is a hydrogen atom, an alkyl group, an aryl group,a quaternary ammonium radical), halogen atom and groups defined in theabove R; provided that at least one of X_(a1), X_(a2), X_(b), Y′, Z′, Y″and Z″ in the same compound is a group having a polar group containingan amino group and X_(a1), X_(a2), X_(b), Y′, Z′, Y″ and Z″ are the sameor different from each other.
 10. The polyphenylene ether-based resincomposition according to any one of claims 1, 2, 3, 4, 5, 6, 7 and 8,wherein the content of the cage silsesquioxane and the partially cleavedstructure of the cage silsesquioxane is from 0.1% by weight to 90% byweight in total.
 11. The polyphenylene ether-based resin compositionaccording to claim 10, wherein the polyphenylene ether-based resin iscomposed solely of a polyphenylene ether resin.
 12. The polyphenyleneether-based resin composition according to claim 10, wherein thepolyphenylene ether-based resin is a polymer alloy of a polyphenyleneether resin and at least one other resin.
 13. The polyphenyleneether-based resin composition according to claim 12, wherein thepolyphenylene ether-based resin is a polymer alloy containing apolyphenylene ether resin and at least one resin selected from apolystyrene-based resin, a polyamide-based resin, a polyester-basedresin, a polyolefin-based resin, and a polyether sulfone-based resin.14. The polyphenylene ether-based resin composition according to claim12, wherein the content of the polyphenylene ether resin in the polymeralloy is 40% by weight or more.
 15. The polyphenylene ether-based resincomposition according to any one of claims 1, 2, 3, 4, 5, 6, 7 and 8,which further contains a cyclic nitrogen compound.
 16. A process forproducing a molded article of a polyphenylene ether-based resincomposition, comprising melt-molding a polyphenylene ether-based resincomposition according to any one of claims 1, 2, 3, 4, 5, 6, 7 and 8.17. A process for producing a molded article of a polyphenyleneether-based resin composition, comprising melt-molding a polyphenyleneether-based resin composition according to claims
 11. 18. A process forproducing a molded article of a polyphenylene ether-based resincomposition, comprising melt-molding a polyphenylene ether-based resincomposition according to claim
 12. 19. A process for producing a moldedarticle of a polyphenylene ether-based resin composition, comprisingmelt-molding a polyphenylene ether-based resin composition according toclaim
 13. 20. A molded article of the polyphenylene ether-based resincomposition according to any one of claims 1, 2, 3, 4, 5, 6, 7 and 8.21. A molded article of the polyphenylene ether-based resin compositionaccording to claim
 11. 22. A molded article of the polyphenyleneether-based resin composition according to claim
 12. 23. A moldedarticle of the polyphenylene ether-based resin composition according toclaim
 13. 24. A process for producing a molded article of apolyphenylene ether-based resin composition, comprising melt-molding apolyphenylene ether-based resin composition according to claim
 10. 25. Amolded article of the polyphenylene ether-based resin compositionaccording to claim
 10. 26. A polyphenylene ether-based resin compositioncomprising a polyphenylene ether-based resin and at least one memberselected from the group consisting of a cage silsesquioxane and apartially cleaved structure of a cage silsesquioxane and furthercomprising a cyclic nitrogen compound.
 27. A process for producing amolded article of a polyphenylene ether-based resin composition,comprising melt-molding a polyphenylene ether-based resin compositioncomprising a polyphenylene ether-based resin and at least one memberselected from the group consisting of a cage silsesquioxane and apartially cleaved structure of a cage silsesquioxane.
 28. A moldedarticle of the polyphenylene ether-based resin composition comprising apolyphenylene ether-based resin and at least one member selected fromthe group consisting of a cage silsesquioxane and a partially cleavedstructure of a cage silsesquioxane.